Organic electroluminescent display device

ABSTRACT

An organic electroluminescent display device including first to fourth pixel regions each including red, green and blue sub-pixel regions, each of the first to fourth pixel regions being divided into first and second column, and the first column being divided into first and second rows, wherein a red sub-pixel region and a green sub-pixel region are respectively arranged in the first and second rows, and a blue sub-pixel region is arranged in the second column; a red emitting layer formed in the red sub-pixel region; a green emitting layer formed in the green sub-pixel region; and a blue emitting layer formed in the blue sub-pixel region.

The present application claims the priority benefit of Korean PatentApplication No. 10-2010-0088059 filed in Republic of Korea on Sep. 8,2010, which is herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to an organic electroluminescent display(OELD) device, and more particularly, to an OELD device having a highaperture ratio and a high resolution.

2. Related Art

An OELD device of new flat panel display devices is a self-emittingtype. The OELD device has excellent characteristics of a view angel, acontrast ratio and so on. Also, since the OELD device does not require abacklight assembly, the OELD device has low weight and low powerconsumption. Moreover, the OELD device has advantages of a high responserate, a low production cost and so on. In addition, all elements of theOELD device are a solid phase, the device is strong against an outerimpact. Particularly, there is a big advantage in a production cost. Afabricating process of the OELD device is very simple and requires adeposition apparatus and an encapsulating apparatus. The OLED device maybe called to as an organic light emitting diode device.

In an active matrix type OELD device, a voltage for controlling anelectric current of a pixel is charged in a storage capacitor such thata level of the electric current is maintained to next frame.

FIG. 1 is a circuit diagram of one sub-pixel region of the related artOELD device. As shown in FIG. 1, an OELD device includes a gate line“GL”, a data line “DL”, a power supply line “PL”, a switching thin filmtransistor (TFT) “Ts”, a storage capacitor “Cst”, a driving TFT “Td”,and an emitting diode “Del”. The gate line “GL” and the data line “DL”cross each other to define a sub-pixel region “SP”. The switching TFT“Ts” is connected to the gate and data line “GL” and “DL”, the drivingTFT “Td” and the storage capacitor “Cst” are connected to the switchingTFT “Ts” and the power line “PL”. The emitting diode “Del” is connectedto the driving TFT “Td”.

When the switching TFT “Ts” is turned on by a gate signal appliedthrough the gate line “GL”, a data signal from the data line “DL” isapplied to the gate electrode of the driving TFT “Td” and an electrodeof the storage capacitor “Cst”. When the driving TFT “Td” is turned onby the data signal, an electric current is supplied to the emittingdiode “Del” from the power line “PL”. As a result, the emitting diode“Del” emits light. In this case, when the driving TFT “Td” is turned on,a level of an electric current applied from the power supply line “PL”to the emitting diode “Del” is determined such that the emitting diode“Del” can produce a gray scale. The storage capacitor “Cst” serves tomaintain the voltage of the gate electrode of the driving TFT “Td” whenthe switching TFT “Ts” is turned off. Accordingly, even if the switchingTFT “Ts” is turned off, a level of an electric current applied from thepower supply line “PL” to the emitting diode “Del” is maintained to nextframe.

To produce full color images, the OELD device includes red, green andblue sub-pixel regions in one pixel region. FIG. 2 is a schematic viewshowing pixel regions of the related art OELD device. As shown in FIG.2, the OELD device 10 includes a plurality of pixel regions “P”. Eachpixel region “P” includes red, green and blue sub-pixel regions “SPr”,“SPg” and “SPb”.

Each pixel region “P” has a rectangular shape to have a horizontallength “H” and a vertical length “V”. The red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb” are arranged in each pixel region “P”along a horizontal direction or a vertical direction. For example, eachof the red, green and blue sub-pixel regions “SPr”, “SPg” and “SPb” hasa horizontal length corresponding to ⅓ of the horizontal length “H” ofthe pixel region “P” and a vertical length corresponding to the verticallength “V” of the pixel region “P”.

Red, green and blue emitting layers 32, 34 and 36 are respectivelyformed in the red, green and blue sub-pixel regions “SPr”, “SPg” and“SPb”. The red, green and blue emitting layers 32, 34 and 36 constitutethe emitting diode “Del” with first and second electrodes (not shown).When the emitting layers are closely disposed, a shadowing problem,i.e., a color mixture in adjacent sub-pixel regions, is generated.Accordingly, each of the emitting layers 32, 34 and 36 has a width “w”,i.e., a horizontal length, and a height “h”, i.e., a vertical length,and is spaced apart from each other by a first distance “d1”.

The red, green and blue emitting layers 32, 34 and 36 are formed by athermal deposition using a shadow mask. In FIG. 2, the red, green andblue emitting layers 32, 34 and 36 are overlapped portions of the firstand second electrodes.

An area of the red, green and blue emitting layers 32, 34 and 36 may belarger than that in FIG. 2. However, since an area of the red, green andblue emitting layers 32, 34 and 36 corresponding to the overlappedportions of the first and second electrodes is effective emittingportions, the red, green and blue emitting layers 32, 34 and 36corresponding to the overlapped portions are shown.

The OELD device 10 display full color images using the red, green andblue emitting layers 32, 34 and 36 in the red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb”.

Recently, to meet requirement for a high resolution, an area of onepixel region “P” and an area of each of the red, green and bluesub-pixel regions “SPr”, “SPg” and “SPb” are reduced.

As a result, an area for the red, green and blue emitting layers 32, 34and 36 is also reduced. The height “h” of each of the red, green andblue emitting layers 32, 34 and 36 substantially corresponds to thevertical length “V” of the pixel region “P” such that there is noproblem. However, since the width “w” of each of the red, green and blueemitting layers 32, 34 and 36 corresponds to the horizontal length “H”of the pixel region “P”, there is a limitation in reducing the width“w”.

Namely, the first distance “d1” between adjacent emitting layers forpreventing the shadowing problem should be maintained when an area ofthe pixel region “P” is reduced because of the requirement of a highresolution.

Accordingly, with a high resolution of the OELD device, an area for thered, green and blue emitting layers 32, 34 and 36 is rapidly reducedsuch that it is difficult to fabricate a fine shadow mask for formingthe red, green and blue emitting layers 32, 34 and 36.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to an OELD device thatsubstantially obviates one or more of the problems due to limitationsand disadvantages of the related art.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. These andother advantages of the invention will be realized and attained by thestructure particularly pointed out in the written description and claimshereof as well as the appended drawings.

In accordance with the present invention, as embodied and broadlydescribed herein, an organic electroluminescent display device includingfirst to fourth pixel regions each including red, green and bluesub-pixel regions, each of the first to fourth pixel regions beingdivided into first and second column, and the first column being dividedinto first and second rows, wherein a red sub-pixel region and a greensub-pixel region are respectively arranged in the first and second rows,and a blue sub-pixel region is arranged in the second column; a redemitting layer formed in the red sub-pixel region; a green emittinglayer formed in the green sub-pixel region; and a blue emitting layerformed in the blue sub-pixel region.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a circuit diagram of one sub-pixel region of the related artOELD device.

FIG. 2 is a schematic view showing pixel regions of the related art OELDdevice.

FIG. 3 is a schematic view showing pixel regions of an OELD deviceaccording to a first embodiment of the present invention.

FIG. 4 is a circuit diagram of one pixel region of an OELD deviceaccording to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view of a sub-pixel region of an OELD deviceaccording to the first embodiment of the present invention.

FIG. 6A is a view showing a shadow mask used for red and green emittinglayers of an OELD device according to the first embodiment of thepresent invention.

FIG. 6B is a view showing a shadow mask used for a blue emitting layersof an OELD device according to the first embodiment of the presentinvention.

FIGS. 7A and 7B are cross-sectional views taken along the linesVIIa-VIIa and VIIb-VIIb in FIG. 6A, respectively.

FIG. 8 is a schematic view showing pixel regions of an OELD deviceaccording to a second embodiment of the present invention.

FIG. 9 is a view showing a shadow mask used for red and green emittinglayers of an OELD device according to the second embodiment of thepresent invention.

FIG. 10 is a schematic view showing pixel regions of an OELD deviceaccording to a third embodiment of the present invention.

FIG. 11 is a view showing a shadow mask used for red and green emittinglayers of an OELD device according to the third embodiment of thepresent invention.

FIG. 12 is a schematic view showing pixel regions of an OELD deviceaccording to a fourth embodiment of the present invention.

FIG. 13 is a view showing a shadow mask used for deep blue and sky blueemitting layers of an OELD device according to the fourth embodiment ofthe present invention.

FIG. 14 is a schematic view showing pixel regions of an OELD deviceaccording to a fifth embodiment of the present invention.

FIG. 15 is a view showing a shadow mask used for red and green emittinglayers of an OELD device according to the fifth embodiment of thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

FIG. 3 is a schematic view showing pixel regions of an OELD deviceaccording to a first embodiment of the present invention.

As shown in FIG. 3, an OELD device 110 includes first to fourth pixelregions “P1”, “P2”, “P3” and “P4” arranged in a matrix shape. Each ofthe first to fourth pixel regions “P1” to “P4” includes red, green andblue sub-pixel regions “SPr”, “SPg” and “SPb”.

Each of the first to fourth pixel regions “P1” to “P4” has a rectangularshape to have a horizontal length “H” and a vertical length “V”. The redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in a first column of each of the first to fourth pixelregions “P1” to “P4”, and the blue sub-pixel region “SPb” is arranged ina second column of each of the first to fourth pixel regions “P1” to“P4”.

Each of the first to fourth pixel regions “P1” to “P4” is divided intothe first and second columns along a horizontal direction, and the firstcolumn is divided into first and second rows along a vertical direction.The red sub-pixel region “SPr” is positioned in the first column and thefirst row, and the green sub-pixel region “SPg” is positioned in thefirst column and the second row. Namely, the red and green sub-pixelregions “SPr” and “SPg” are alternately arranged with each other in thepixel regions adjacent along the vertical direction. In other words, thered and green sub-pixel regions “SPr” and “SPg” are alternately arrangedin the first column of the first and third pixel regions “P1” and “P3”.In addition, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged in the first column of the second and fourth pixelregions “P2” and “P4”. As a result, in the first column, one greensub-pixel region “SPg” is positioned between two adjacent red sub-pixelregions “SPr”. The blue sub-pixel region “SPb” is positioned in thesecond column. Red, green and blue emitting layers 132, 134 and 136 arerespectively formed in the red, green and blue sub-pixel regions “SPr”,“SPg” and “SPb”.

The red, green and blue emitting layers 132, 134 and 136 constitute anemitting diode “Del” (of FIG. 5) with a first electrode 130 (of FIG. 5)and a second electrode 138 (of FIG. 5). To prevent the shadowingproblem, the emitting layers 132, 134 and 136 are spaced apart from eachother by a first distance “d1”. For example, the first distance “d1” maybe about 22 micrometers.

Each of the red and green emitting layers 132 and 134 has a first width“w1”, i.e., a horizontal length, and a first height “h1”, i.e., avertical length. The blue emitting layer 136 has a second width “w2” anda second height “h2”. Namely, each of the red, green and blue emittinglayers 132, 134 and 136 has a rectangular shape. The red and greensub-pixel regions “SPr” and “SPg” are positioned in the first and secondrows of the first column such that the first width “w1” is larger thanthe first height “h1”. On the contrary, the blue sub-pixel region “SPb”is positioned in an entire of the second column such that the secondwidth “w2” is smaller than the second height “h2”.

The red, green and blue emitting layers 132, 134 and 136 are formed by athermal deposition using a shadow mask. In FIG. 3, the red, green andblue emitting layers 132, 134 and 136 are overlapped portions of thefirst and second electrodes.

An area of the red, green and blue emitting layers 132, 134 and 136 maybe larger than that in FIG. 3. However, since an area of the red, greenand blue emitting layers 132, 134 and 136 corresponding to theoverlapped portions of the first and second electrodes 130 and 138 iseffective emitting portions, the red, green and blue emitting layers132, 134 and 136 corresponding to the overlapped portions are shown.

Particularly, when the first electrode 130 is exposed through an opening128 a (of FIG. 5) of a bank 128 (of FIG. 5), the red, green and blueemitting layers 132, 134 and 136 contact the exposed portion of thefirst electrode 130 and the second electrode 138 is formed on an entiresurface of the red, green and blue emitting layers 132, 134 and 136 asone-body, the overlapped portion of the first and second electrodes 130and 138 may be equal to the opening 128 a of the bank 128.

As mentioned above, in the OELD device 110 according to the firstembodiment of the present invention, each of the first pixel regions“P1” to “P4” is divided into the first and second columns, and the firstcolumn is divided into the first and second rows. Then, the red andgreen sub-pixel regions “SPr” and “SPg” are respectively disposed inregions defined by the first column and the first and second rows, andthe blue sub-pixel region “SPb” is disposed in a region defined by thesecond column. In addition, the red, green and blue emitting layers 132,134 and 136 are formed in the red, green and blue sub-pixel regions“SPr”, “SPg” and “SPb”, respectively.

Accordingly, with compared to the related art OELD device, where threesub-pixel regions are arranged along a direction, there is a margin inreduction of the width of the sub-pixel regions. As a result, there is amargin for requirement of a high resolution. Namely, when an area, e.g.,a width, of the red, green and blue sub-pixel regions “SPr”, “SPg” and“SPb” is reduced with requirement of a high resolution, there is amargin in reduction of the width of the red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb” such that a shadow mask for forming thered, green and blue emitting layers 132, 134 and 136 is easilyfabricated.

FIG. 4 is a circuit diagram of one pixel region of an OELD deviceaccording to the first embodiment of the present invention, and FIG. 5is a cross-sectional view of a sub-pixel region of an OELD deviceaccording to the first embodiment of the present invention.

As shown in FIG. 4, the OELD device 110 includes first and second gatelines “GL1” and “GL2”, first to third data lines “DL1”, “DL2” and “DL3”and first to third power lines “PL1”, “PL2” and “PL3”. A regionsurrounded by the first and second gate lines “GL1” and GL2″, the firstdata line “DL1” and the third power line “PL3” is defined as a pixelregion

The pixel region “P” is divided into the first and second columns, andthe first column is divided into the first and second rows. The red andgreen sub-pixel regions “SPr” and “SPg” are defined in the first andsecond rows of the first column, respectively, and the blue sub-pixelregion “SPb” is defined in the second column.

In each of the red, green and blue sub-pixel regions “SPr”, “SPg” and“SPb”, a switching TFT “Ts”, a driving TFT “Td”, a storage capacitor“Cst” and an emitting diode “Del” are formed. A position of theswitching TFT “Ts”, the driving TFT “Td” and the storage capacitor “Cst”is not limited in the respective sub-pixel region. For example, theswitching TFT “Ts”, the driving TFT “Td” and the storage capacitor “Cst”as elements of the red sub-pixel region “SPr” may be positioned in thegreen sub-pixel region “SPg” or the blue sub-pixel region “SPb”.

In FIG. 4, the first power line “PL1”, the second data line “DL2”, thesecond power line “PL2” and the third data line “DL3” are positioned inorder between the first data line “DL1” and the third power line “PL3”.However, there is no limitation in the data lines “DL1” to “DL3” and thepower lines “PL1” to “PL3”. For example, the second data line “DL2” ispositioned in a position of the second power line “PL2” without thesecond power line “PL2”, and the driving TFT “Td” in the green sub-pixelregion “SPg” is connected to the first power line “PL1”. Namely, the redand green sub-pixel regions “SPr” and “SPg” share the first power line“PL1” without the second power line “DL2”.

In FIG. 4, the switching TFT “Ts”, the driving TFT “Td”, the storagecapacitor “Cst” and the emitting diode “Del” in the red sub-pixel region“SPr” is driven by signals from the first gate line “GL1” and the firstdata line “DL1”, and the driving TFT “Td”, the storage capacitor “Cst”and the emitting diode “Del” in the green sub-pixel region “SPg” isdriven by signals from the first gate line “GL1” and the second dataline “DL1”. The driving TFT “Td”, the storage capacitor “Cst” and theemitting diode “Del” in the blue sub-pixel region “SPb” is driven bysignals from the first gate line “GL1” and the third data line “DL3”,

Referring to FIG. 5, the OELD device 110 includes a substrate 111 ofglass or plastic, the driving TFT “Td” over the substrate 111, and theemitting diode “Del” connected to the driving TFT “Td”.

Although not shown, on the substrate 111, the gate lines “GL1” and “GL2”(of FIG. 4), the data lines “DL1” to “DL3” (of FIG. 4), the power lines“PL1” to “PL3” (of FIG. 4), and the switching TFT “Ts” are formed.

In more detail, on the substrate 111, a semiconductor layer 112including an active region 112 a, a source region 112 b and a drainregion 112 c is formed, and a gate insulating layer 114 covering anentire surface of the substrate 111 is formed to cover the semiconductorlayer 112.

The semiconductor layer 112 is formed of a semiconductor material, forexample, amorphous silicon or polycrystalline silicon. The active region112 a is formed of intrinsic silicon, and each of the source and drainregions 112 b and 112 c is formed of impurity-doped silicon. The gateinsulating layer 114 may be formed of an inorganic insulating material,for example, silicon oxide or silicon nitride.

A gate electrode 116 is formed on the gate insulating layer 114 tocorrespond to the semiconductor layer 112, and an interlayer insulatinglayer 118 is formed on an entire surface of the substrate 111 to coverthe gate electrode 116. The gate electrode 116 may be formed of aconductive metallic material, for example, aluminum (Al) or Al alloy.The interlayer insulating layer 118 may be formed of an inorganicinsulating material, for example, silicon oxide or silicon nitride, oran organic insulating material, for example, benzocyclobutene or acrylicresin. The interlayer insulating layer 118 includes a source regioncontact hole 120 a exposing the source region 112 b and a drain regioncontact hole 120 b exposing the drain region 112 c.

A source electrode 120, the drain electrode 122 and a data line 124 areformed on the interlayer insulating layer 118. The source electrode 120is connected to the source region 112 b through the source regioncontact hole 120 a, and the drain electrode 122 is connected to thedrain region 112 c through the drain region contact hole 120 b.

The semiconductor layer 112, the gate electrode 116, the sourceelectrode 120 and the drain electrode 122 constitute the driving TFT“Td”. Although not shown, the switching TFT “Ts” may have substantiallythe same structure as the driving TFT “Td”. The gate line is formed ofthe same material and at the same layer as the gate electrode 116.

A passivation layer 126 is formed on an entire surface of the substrate111 to cover the driving TFT “Td”. The passivation layer 126 may beformed an inorganic insulating material, for example, silicon oxide orsilicon nitride, or an organic insulating material, for example,benzocyclobutene or acrylic resin. The passivation layer 126 includes adrain electrode contact hole 126 a exposing the drain electrode 122.

The first electrode 130 is formed on the passivation layer 126 tocorrespond to the pixel region “P”. The first electrode 130 is connectedto the drain electrode 122 through the drain electrode contact hole 126a.

A bank 128 is formed at a boundary of the first electrode 130. The bank128 includes an opening 128 a exposing the first electrode 130. The bank128 may be formed of an inorganic insulating material, for example,silicon oxide or silicon nitride, or an organic insulating material, forexample, benzocyclobutene or acrylic resin.

On the first electrode 130 and in the opening 128 a, the red, green andblue emitting layers 132, 134 and 136 are formed in the red, green andblue sub-pixel regions “SPr”, “SPg” and “SPb”, respectively. The secondelectrode 138 is formed on an entire surface of the substrate 222 tocover the red, green and blue emitting layers 132, 134 and 136.

The first electrode 130, each of the emitting layers 132, 134 and 136,and the second electrode 138 constitute the emitting diode “Del”, andthe first and second electrodes 130 and 138 are formed of conductivematerials having different work functions.

An electron and a hole are provided into a portion of each of theemitting layers 132, 134 and 136, which contacts the first electrode130, such that the portion of the each of the emitting layers 132, 134and 136 emits light. When an emitting area, by which an aperture ratiois determined, of each of the red, green and blue emitting layers 132,134 and 136 respectively in the red, green and blue sub-pixel regions“SPr”, “SPg” and “SPc” is considered, an important fact is an exposedarea of the first electrode 130 through the opening 128 a of the bank128. Accordingly, the red, green and blue emitting layers 132, 134 and136 corresponding to the opening 128 a of the bank 128 are shown in FIG.3.

The first and second electrodes 130 and 138 respectively serve as ananode and a cathode. One of the first and second electrodes 130 and 138serving the anode has a higher work function than the other of the firstand second electrodes 130 and 138. For example, the anode may be formedof indium-tin-oxide (ITO), and the cathode may be formed of aluminum.

Each of the emitting layers 132, 134 and 136 may includes an electroninjection layer (EIL), an emitting material layer (EML) and a holeinjection layer (HIL) to improve an emission efficiency. Anothersubstrate for encapsulation is attached to the substrate 111 such thatthe OELD 110 is obtained.

A shadow mask for forming the red, green and blue emitting layers 132,134 and 136 is illustrated with reference to FIGS. 6A and 6B with FIG.3. FIG. 6A is a view showing a shadow mask used for red and greenemitting layers of an OELD device according to the first embodiment ofthe present invention, and FIG. 6B is a view showing a shadow mask usedfor a blue emitting layers of an OELD device according to the firstembodiment of the present invention.

As shown in FIG. 6A, a first shadow mask 160, which is used for formingthe red emitting layer 132 and/or the green emitting layer 134, includesa plurality of first opening portions 162 for transmitting an emittingmaterial and a first blocking portion 164. The first blocking portion164 surrounds the first opening portions 162 and blocks the emittingmaterial.

An align position of the first shadow mask 160 for the red emittinglayer 132 is different from an align position of the first shadow mask160 for the green emitting layer 134. The first shadow mask 160 is movedalong a vertical direction or a horizontal direction to form one of thered and green emitting layers 132 and 134 after forming the other of thered and green emitting layers 132 and 134.

Each of the first opening portions 162 corresponds to the red emittinglayer 132 or the green emitting layer 134 in each of the pixel region“P1” to “P4”. Each of the first opening portions 162 has a sizesubstantially equal to the first width “w1” and the first height “h1”.Accordingly, adjacent first opening regions 162 along a horizontaldirection are spaced apart from each other by a first length “L1”corresponding to a summation of the second width “w2” of the blueemitting layer 136 and twice of the first distance “d1”. (L1˜w2+2*d1) Inaddition, adjacent first opening portions 162 along a vertical directionare spaced apart from each other by a second length “L2” correspondingto a summation of the first height “h1” of the red emitting layer 132 orthe green emitting layer 134 and twice of the first distance “d1”.(L2˜h1+2*d1) The first length “L1” may be smaller than the second length“L2”. Alternatively, each of the first opening portions 162 has a sizelarger the first width “w1” and the first height “h1”.

On the other hand, as shown in FIG. 6B, a second shadow mask 170, whichis used for forming the blue emitting layer 136, includes a plurality ofsecond opening portions 172 for transmitting an emitting material and asecond blocking portion 174. The second blocking portion 174 surroundsthe second opening portions 172 and blocks the emitting material.

Each of the second opening portions 172 corresponds to the blue emittinglayer 136 in each of the pixel regions “P1” to “P4”. Each of the secondopening portions 172 has a size substantially equal to the second width“w2” and the second height “h2”. Accordingly, adjacent second openingregions 172 along a horizontal direction are spaced apart from eachother by a third length “L3” corresponding to a summation of the firstwidth “w1” of the red emitting layer 132 or the green emitting layer 134and twice of the first distance “d1”. (L3˜w1+2*d1) In addition, adjacentsecond opening regions 172 along a vertical direction are spaced apartfrom each other by a fourth length “L4” corresponding to the firstdistance “d1”. (L4˜d1) Alternatively, each of the second openingportions 172 has a size larger the second width “w2” and the secondheight “h2”.

Unfortunately, when the resolution of the OELD device is furtherincreased, a length or a distance between adjacent first openingportions 162 or between the adjacent second opening portions 172 isreduced such that a twisted problem is generated. Particularly, when thefirst and second lengths “L1” and “L2” between the first openingportions 162 of the first shadow mask 160 are decreased, thicknesses ofthe first blocking portion 164 is differently decreased such that thetwisted problem becomes serious. This problem is illustrated withreference to FIGS. 7A and 7B with FIG. 6A.

FIGS. 7A and 7B are cross-sectional views taken along the linesVIIa-VIIa and VIIb-VIIb in FIG. 6A, respectively. As shown in FIGS. 7Aand 7B, when the first shadow mask 160 including the first openingportions 162 and the first blocking portion 164 is formed by etching ametal plate (not shown), which has a first thickness “t1”, the firstlength “L1”, which is a horizontal distance between adjacent firstopening portions 162, may be larger than the second length “L2” which isa vertical distance between adjacent first opening portions 162. Inaddition, the first width “w1” of the first opening portion 162 may belarger than the first height “h1” of the first opening portion 162. Forexample, the first length “L1”, the second length “L2”, the first width“w1” and the first height “h1” may be about 38 micrometers, about 46.5micrometers, about 49 micrometers and about 41.5 micrometers,respectively.

When the first opening portions 162 are formed, a taper angel “θ” shouldbe maintained as about 59 degrees to obtain a desired emitting layers.Since the width and height of the first opening portion 162 aredifferent and the horizontal distance and the vertical distance betweenthe adjacent first opening portions 162 are different, the thickness ofthe blocking portion 164 is also different along the horizontaldirection and the vertical direction.

Namely, the first width “w1” of the first opening 162 is larger than thefirst height “h1” of the first opening 162 such that the metal plate ismore etched with respect to the horizontal direction. As a result, theblocking portion 164 has a second thickness “t2” along the horizontaldirection and a third thickness “t3” along the vertical direction. Thesecond thickness “t2” is smaller than the first thickness “t1” of themetal plate, and the third thickness “t3” is larger than the secondthickness “t2”. For example, the second and third thicknesses “t2” and“t3” may be about 31.2 micrometers and about 38.2 micrometers,respectively.

When the first shadow mask 160 is used for forming the emitting layers,the first shadow mask 160 is fixed by a frame. To fix the first shadowmask 160 to the frame, the first shadow mask 160 should be stretched.

To prevent deformation of the first shadow mask 160 when the firstshadow mask 160 is stretched, the first shadow mask 160 should have athickness of about 40 micrometers. However, a thickness of the abovefirst shadow mask 160 is smaller than 40 micrometers, there may bedeformation in the first shadow mask 160 when the first shadow mask 160is stretched. In addition, the first shadow mask 160 has a difference ina thickness along the horizontal direction and the vertical direction,there is a difference in expansion such that deformation of the firstshadow mask 160 is further serious. The deformation of the first shadowmask 160 causes a size difference of the first opening portions 162 suchthat there are problems in the emitting layers 132 and 134.

To prevent the deformation of the shadow mask, the red and greensub-pixel regions are alternately arranged. This arrangement of thesub-pixel regions is illustrated with reference to following drawings.

FIG. 8 is a schematic view showing pixel regions of an OELD deviceaccording to a second embodiment of the present invention. As shown inFIG. 8, an OELD device 210 includes first to fourth pixel regions “P1”to “P4” arranged in a matrix shape. Each of the first to fourth pixelregions “P1” to “P4” includes red, green and blue sub-pixel regions“SPr”, “SPg” and “SPb”.

Each of the first to fourth pixel regions “P1” to “P4” has a rectangularshape to have a horizontal length “H” and a vertical length “V”. The redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in a first column of each of the first to fourth pixelregions “P1” to “P4”, and the blue sub-pixel region “SPb” is arranged ina second column of each of the first to fourth pixel regions “P1” to“P4”.

Each of the first to fourth pixel regions “P1” to “P4” is divided intothe first and second columns along a horizontal direction, and the firstcolumn is divided into first and second rows along a vertical direction.The red sub-pixel region “SPr” and the green sub-pixel region “SPg” arealternately arranged in the first and second rows of the first column.Namely, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe vertical direction. In other words, the red and green sub-pixelregions “SPr” and “SPg” are alternately arranged in the first column ofthe first and third pixel regions “P1” and “P3”. In addition, the redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in the first column of the second and fourth pixelregions “P2” and “P4”. As a result, in the first column, one greensub-pixel region “SPg” is positioned between two adjacent red sub-pixelregions “SPr”.

For example, when the red and green sub-pixel regions “SPr” and “SPg”are respectively disposed in the first and second rows of the firstcolumn in the first pixel region “P1”, the green and red sub-pixelregions “SPg” and “SPr” are respectively disposed in the first andsecond rows of the first column in the third pixel region “P3” which isadjacent to the first pixel region “P1” along the vertical direction.

In addition, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe horizontal direction. For example, when the red and green sub-pixelregions “SPr” and “SPg” are respectively disposed in the first andsecond rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the secondpixel region “P2” which is adjacent to the first pixel region “P1” alongthe horizontal direction.

With the above sub-pixel region arrangement, a distance between adjacentred sub-pixel regions “SPr” and between adjacent green sub-pixel regions“SPg” is increased such that a fabrication of the shadow mask becomeseasy.

The blue sub-pixel region “SPb” is positioned in the second column. Red,green and blue emitting layers 232, 234 and 236 are respectively formedin the red, green and blue sub-pixel regions “SPr”, “SPg” and “SPb”. Thered, green and blue emitting layers 232, 234 and 236 constitute anemitting diode (not shown) with a first electrode (not shown) and asecond electrode (not shown). To prevent the shadowing problem, theemitting layers 232, 234 and 236 are spaced apart from each other by afirst distance “d1”. For example, the first distance “d1” may be about22 micrometers.

Each of the red and green emitting layers 232 and 234 has a first width“w1”, i.e., a horizontal length, and a first height “h1”, i.e., avertical length. The blue emitting layer 236 has a second width “w2” anda second height “h2”. Namely, each of the red, green and blue emittinglayers 232, 234 and 236 has a rectangular shape. The red and greensub-pixel regions “SPr” and “SPg” are positioned in the first column ofeach of the pixel regions “P1” to “P4” such that the first width “w1” islarger than the first height “h1”. On the contrary, the blue sub-pixelregion “SPb” is positioned in an entire of the second column such thatthe second width “w2” is smaller than the second height “h2”.

The red, green and blue emitting layers 232, 234 and 236 are formed by athermal deposition using a shadow mask. In FIG. 8, the red, green andblue emitting layers 232, 234 and 236 are overlapped portions of thefirst and second electrodes.

As mentioned above, in the OELD device 210 according to the secondembodiment of the present invention, the first and second columns aredefined by dividing each of the first to fourth pixel regions “P1” to“P4”, and the first and second rows are defined by dividing the firstcolumn. The red and green sub-pixel regions “SPr” and “SPg” arealternately arranged in the first column. The red and green sub-pixelregions “SPr” and “SPg” are alternately arranged with each other alongthe vertical direction and the horizontal direction. The red, green andblue emitting layers 232, 234 and 236 are respectively formed in thered, green and blue sub-pixel regions “SPr”, “SPg” and “SPb”.

Accordingly, with compared to the related art OELD device, where threesub-pixel regions are arranged along a direction, there is a margin inreduction of the width of the sub-pixel regions. As a result, there is amargin for requirement of a high resolution. Namely, when an area, e.g.,a width, of the red, green and blue sub-pixel regions “SPr”, “SPg” and“SPb” is reduced with requirement of a high resolution, there is amargin in reduction of the width of the red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb” such that a shadow mask for forming thered, green and blue emitting layers 232, 234 and 236 is easilyfabricated.

In addition, a distance between adjacent red sub-pixel regions “SPr” andbetween adjacent green sub-pixel regions “SPg” is increased, the shadowmask for the red and green sub-pixel regions “SPr” and “SPg” is furthereasily fabricated.

FIG. 9 is a view showing a shadow mask used for red and green emittinglayers of an OELD device according to the second embodiment of thepresent invention. The shadow mask used for red and green emittinglayers is illustrated with FIGS. 8 and 9. The shadow mask used for theblue emitting layer is same as that in the first embodiment.

As shown in FIG. 9, the shadow mask 260 used for forming the red andgreen sub-pixel regions 232 and 234 includes a plurality of openingportions 262 for transmitting an emitting material and a blockingportion 264. An align position of the shadow mask 260 for the redemitting layer 232 is different from an align position of the shadowmask 260 for the green emitting layer 234. The shadow mask 260 is movedalong a vertical direction or a horizontal direction to form one of thered and green emitting layers 232 and 234 after forming the other of thered and green emitting layers 232 and 234.

Each of the opening portions 262 corresponds to the red emitting layer232 or the green emitting layer 234 in each of the pixel region “P1” to“P4”. Each of the opening portions 262 has a size substantially equal tothe first width “w1” and the first height “h1”. Accordingly, adjacentopening regions 262 along a vertical direction are spaced apart fromeach other by a second length “L2” corresponding to a summation of thefirst height “h1” of the red emitting layer 232 or the green emittinglayer 234 and twice of the first distance “d1”. (L2˜h1+2*d1) Inaddition, adjacent opening portions 262 along a diagonal direction arespaced apart from each other by a fifth length “L5” which is calculatedby a summation of the second width “w2” of the blue emitting layer 236and twice of the first distance “d1” and the first distance “d1”.(L5˜((w2+2*d1)²+d1 ²)^(1/2) Alternatively, each of the first openingportions 162 has a size larger the first width “w1” and the first height“h1”.

The fifth length “L5” is larger than the first length “L1”, which is ahorizontal distance between adjacent first opening portions 162 in thefirst embodiment, and closer to the second length “L2” than the firstlength “L1”.

Namely, a distance between adjacent opening portions 262 is increased,the shadow mask 260 is easily fabricated with a higher resolution. Inaddition, since the distances between adjacent opening portions 262along the vertical direction and the diagonal direction become close, athickness difference of the blocking portion 264 of the shadow mask 260is reduced such that deformation of the shadow mask 260 is prevented.

FIG. 10 is a schematic view showing pixel regions of an OELD deviceaccording to a third embodiment of the present invention. As shown inFIG. 10, an OELD device 310 includes first to fourth pixel regions “P1”to “P4” arranged in a matrix shape. Each of the first to fourth pixelregions “P1” to “P4” includes red, green and blue sub-pixel regions“SPr”, “SPg” and “SPb”.

Each of the first to fourth pixel regions “P1” to “P4” has a rectangularshape to have a horizontal length “H” and a vertical length “V”. The redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in a first column of each of the first to fourth pixelregions “P1” to “P4”, and the blue sub-pixel region “SPb” is arranged ina second column of each of the first to fourth pixel regions “P1” to“P4”.

Each of the first to fourth pixel regions “P1” to “P4” is divided intothe first and second columns along a horizontal direction, and the firstcolumn is divided into first and second rows along a vertical direction.The red sub-pixel region “SPr” and the green sub-pixel region “SPg” arealternately arranged in the first and second rows of the first column.Namely, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe vertical direction. In other words, the red and green sub-pixelregions “SPr” and “SPg” are alternately arranged in the first column ofthe first and third pixel regions “P1” and “P3”. In addition, the redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in the first column of the second and fourth pixelregions “P2” and “P4”. As a result, in the first column, one greensub-pixel region “SPg” is positioned between two adjacent red sub-pixelregions “SPr”.

In the vertically-arranged pixel regions “P1” and “P3” or “P2” and “P4”,the same color sub-pixel regions are arranged to be closer thandifferent color sub-pixel regions. For example, when the red and greensub-pixel regions “SPr” and “SPg” are respectively disposed in the firstand second rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the thirdpixel region “P3”. In this case, a distance between the red and greensub-pixel regions “SPr” and “SPg” in each of the first and third pixelregions “P1” and “P3” is larger than that between the green sub-pixelregion “SPg” in the first pixel region “P1” and the green sub-pixelregion “SPg” in the second pixel region “P2”.

In addition, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe horizontal direction. For example, when the red and green sub-pixelregions “SPr” and “SPg” are respectively disposed in the first andsecond rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the secondpixel region “P2” which is adjacent to the first pixel region “P1” alongthe horizontal direction.

Similarly, the red and green sub-pixel regions “SPr” and “SPg” arerespectively arranged in the first and second rows of the first columnin the fourth pixel region “P4”. In this case, a distance between thered and green sub-pixel regions “SPr” and “SPg” in each of the secondand fourth pixel regions “P2” and “P4” is larger than that between thered sub-pixel region “SPr” in the second pixel region “P2” and the redsub-pixel region “SPr” in the fourth pixel region “P4”.

The same color sub-pixel regions are closely arranged and closelyarranged sub-pixel regions corresponds to one opening portion of theshadow mask such that a size of each opening portion of the shadow maskand a distance between opening portions of the shadow mask is increased.As a result, a fabrication of the shadow mask becomes further easy.

In addition, by alternately arranging the red and green sub-pixelregions “SPr” and “SPg” along the horizontal direction, a distancebetween adjacent red sub-pixel regions “SPr” and between adjacent greensub-pixel regions “SPg” is increased such that a fabrication of theshadow mask becomes easy.

The blue sub-pixel region “SPb” is positioned in the second column. Red,green and blue emitting layers 332, 334 and 336 are respectively formedin the red, green and blue sub-pixel regions “SPr”, “SPg” and “SPb”. Thered, green and blue emitting layers 332, 334 and 336 constitute anemitting diode (not shown) with a first electrode (not shown) and asecond electrode (not shown). To prevent the shadowing problem, theemitting layers 332, 334 and 336 are spaced apart from each other by afirst distance “d1”.

Since there is no shadowing problem in the same color emitting layers,the same color emitting layers are spaced apart from each other by asecond distance “d2” being smaller than the first distance “d1”. Forexample, the first distance “d1” may be about 22 micrometers, and thesecond distance “d2” may be about 13 micrometers.

For example, when the red and green sub-pixel regions “SPr” and “SPg”are respectively disposed in the first and second rows of the firstcolumn in the first pixel region “P1” and the green and blue sub-pixelregions “SPg” and “SPr” are respectively disposed in the first andsecond rows of the first column in the third pixel region “P3”, the redand green emitting layers 332 and 334 in the first pixel region “P1” andthe green and red emitting layers 334 and 332 in the third pixel region“P3” are spaced apart from each other by the first distance “d1”,respectively, and the green emitting layer 334 in the first pixel region“P1” and the green emitting layer 334 in the third pixel region “P3” arespaced apart from each other by the second distance “d2” being smallerthan the first distance “d1”.

Accordingly, with the same size pixel region, a size of each of the redand green emitting layers 332 and 334 in the third embodiment is largerthan a size of each of the red and green emitting layers 232 and 234 inthe second embodiment.

Namely, each of the red and green emitting layers 332 and 334 has afirst width “w1”, which is equal to the first width “w1” in the secondembodiment, and a third height “h3”, which is larger than the firstheight “h1” in the second embodiment. The blue emitting layer 336 hasthe second width “w2” and the second height “h2” being larger than thesecond width “w2”.

In FIG. 10, the first width “w1” is larger than the third height “h3”.Alternatively, when the third height “h3” is further increased, thethird height “h3” may be larger than the first width “w1”.

The red, green and blue emitting layers 332, 334 and 336 are formed by athermal deposition using a shadow mask. In FIG. 10, the red, green andblue emitting layers 332, 334 and 336 are overlapped portions of thefirst and second electrodes.

As mentioned above, in the OELD device 310 according to the thirdembodiment of the present invention, the first and second columns aredefined by dividing each of the first to fourth pixel regions “P1” to“P4”, and the first and second rows are defined by dividing the firstcolumn. The red and green sub-pixel regions “SPr” and “SPg” arealternately arranged in the first column. The red and green sub-pixelregions “SPr” and “SPg” are alternately arranged with each other alongthe vertical direction and the horizontal direction. In the first columnof vertically adjacent pixel regions “P1” and “P3” or “P2” and “P4”, thesame color sub-pixel regions are arranged to be closer than differentcolor sub-pixel regions. The red, green and blue emitting layers 332,334 and 336 are respectively formed in the red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb”.

Accordingly, with compared to the related art OELD device, where threesub-pixel regions are arranged along a direction, there is a margin inreduction of the width of the sub-pixel regions. As a result, there is amargin for requirement of a high resolution. Namely; when an area, e.g.,a width and a height, of the red, green and blue sub-pixel regions“SPr”, “SPg” and “SPb” is reduced with requirement of a high resolution,there is a margin in reduction of the area of the red, green and bluesub-pixel regions “SPr”, “SPg” and “SPb” such that a shadow mask forforming the red, green and blue emitting layers 332, 334 and 336 iseasily fabricated.

In addition, the same color sub-pixel regions are closely arranged andclosely arranged sub-pixel regions corresponds to one opening portion ofthe shadow mask such that a size of each opening portion of the shadowmask and a distance between opening portions of the shadow mask isincreased. Moreover, by alternately arranging the red and greensub-pixel regions “SPr” and “SPg” along the horizontal direction, adistance between adjacent red sub-pixel regions “SPr” and betweenadjacent green sub-pixel regions “SPg” is increased. As a result, afabrication of the shadow mask used for the red and green emittinglayers 342 and 344 becomes easy.

In the OEDL device 310 according to the third embodiment of the presentinvention, the red and green emitting layers 332 and 334 are formedusing the above shadow mask. FIG. 11 is a view showing a shadow maskused for red and green emitting layers of an OELD device according tothe third embodiment of the present invention. The shadow mask used forthe blue emitting layer is same as that in the first and secondembodiments.

Referring to FIG. 11 with FIG. 10, the shadow mask 360 used for formingthe red and green emitting layers 332 and 334 includes a plurality ofopening portions 362 for transmitting an emitting material and ablocking portion 364. An align position of the shadow mask 360 for thered emitting layer 332 is different from an align position of the shadowmask 360 for the green emitting layer 334. The shadow mask 360 is movedalong a vertical direction or a horizontal direction to form one of thered and green emitting layers 332 and 334 after forming the other of thered and green emitting layers 332 and 334.

Each of the opening portions 362 corresponds to two adjacent redemitting layers 332 or two adjacent green emitting layers 334 invertically adjacent pixel regions. Each of the opening portions 362 hasthe first width “w1” and a fourth height “h4”. The fourth height “h4” isequal to a summation of twice of the third height “h3” of the redemitting layer 332 or the green emitting layer 334 and the seconddistance “d2”. (h4˜2*h3+d2) Alternatively, the fourth height “h4” may belarger than a summation of heights of two adjacent red emitting layers332 and a distance between two adjacent red emitting layers 332.

The adjacent opening portions 362 in the shadow mask 360 is space apartfrom each other along a diagonal direction by a fifth length “L5” whichis calculated by a summation of the second width “w2” of the blueemitting layer 336 and twice of the first distance “d1” and the firstdistance “d1”. (L5˜((w2+2*d1)²+d1 ²)^(1/2) In addition, the adjacentopening portions 362 in the shadow mask 360 is space apart from eachother along a vertical direction by a sixth length “L6” corresponding toa summation of twice of the third height “h3” of the red emitting layer332 or the green emitting layer 334, twice of the first distance “d1”and the second distance “d2”. (L6˜2*h3+2*d1+d2)

The fourth height “h4” of each opening portion 362 is larger than thefirst height “h1” of each of the opening portions 162 and 262 in thefirst and second embodiments, and the sixth length “L6”, which is adiagonal distance between adjacent opening portions 362, is larger thanthe second length “L2”, which is a distance between vertically adjacentopening portions 162 and 262, in the first and second embodiments.

Namely, a distance between adjacent opening portions 362 and a size ofthe opening portion 362 are increased, the shadow mask 360 is easilyfabricated with a higher resolution. In addition, since the distancesbetween adjacent opening portions 362 along the vertical direction andthe diagonal direction become close, a thickness difference of theblocking portion 364 of the shadow mask 360 is reduced such thatdeformation of the shadow mask 360 is prevented.

FIG. 12 is a schematic view showing pixel regions of an OELD deviceaccording to a fourth embodiment of the present invention. The OELDdevice in FIG. 12 includes two blue sub-pixel regions to furtherincrease a distance between the opening portions of the shadow mask.

As shown in FIG. 12, an OELD device 410 includes first to fourth pixelregions “P1” to “P4” arranged in a matrix shape. Each of the first tofourth pixel regions “P1” to “P4” includes red, green and deep bluesub-pixel regions “SPr”, “SPg” and “SPb1” or red, green and sky bluesub-pixel regions “SPr”, “SPg” and “SPb2”.

Each of the first to fourth pixel regions “P1” to “P4” has a rectangularshape to have a horizontal length “H” and a vertical length “V”. The redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in a first column of each of the first to fourth pixelregions “P1” to “P4”. In the vertically adjacent pixel regions, the samecolor sub-pixel regions are closely arranged. The deep blue sub-pixelregion “SPb1” is arranged in a second column of one pixel region, andthe sky blue sub-pixel region “SPb2” is arranged in a second column ofanother one pixel region. The deep blue sub-pixel region “SPb1” and thesky blue sub-pixel region “SPb2” are alternately arranged with eachother along the vertical direction and the horizontal direction.

Each of the first to fourth pixel regions “P1” to “P4” is divided intothe first and second columns along a horizontal direction, and the firstcolumn is divided into first and second rows along a vertical direction.The red sub-pixel region “SPr” and the green sub-pixel region “SPg” arealternately arranged in the first and second rows of the first column.Namely, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe vertical direction. In other words, the red and green sub-pixelregions “SPr” and “SPg” are alternately arranged in the first column ofthe first and third pixel regions “P1” and “P3”. In addition, the redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in the first column of the second and fourth pixelregions “P2” and “P4”. As a result, in the first column, one greensub-pixel region “SPg” is positioned between two adjacent red sub-pixelregions “SPr”.

In the vertically-arranged pixel regions “P1” and “P3” or “P2” and “P4”,the same color sub-pixel regions are arranged to be closer thandifferent color sub-pixel regions. For example, when the red and greensub-pixel regions “SPr” and “SPg” are respectively disposed in the firstand second rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the thirdpixel region “P3”. In this case, a distance between the red and greensub-pixel regions “SPr” and “SPg” in each of the first and third pixelregions “P1” and “P3” is larger than that between the green sub-pixelregion “SPg” in the first pixel region “P1” and the green sub-pixelregion “SPg” in the second pixel region “P2”.

In addition, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe horizontal direction. For example, when the red and green sub-pixelregions “SPr” and “SPg” are respectively disposed in the first andsecond rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the secondpixel region “P2” which is adjacent to the first pixel region “P1” alongthe horizontal direction.

Similarly, the red and green sub-pixel regions “SPr” and “SPg” arerespectively arranged in the first and second rows of the first columnin the fourth pixel region “P4”. In this case, a distance between thered and green sub-pixel regions “SPr” and “SPg” in each of the secondand fourth pixel regions “P2” and “P4” is larger than that between thered sub-pixel region “SPr” in the second pixel region “P2” and the redsub-pixel region “SPr” in the fourth pixel region “P4”.

The same color sub-pixel regions are closely arranged and closelyarranged sub-pixel regions corresponds to one opening portion of theshadow mask such that a size of each opening portion of the shadow maskand a distance between opening portions of the shadow mask is increased.As a result, a fabrication of the shadow mask becomes further easy.

In addition, by alternately arranging the red and green sub-pixelregions “SPr” and “SPg” along the horizontal direction, a distancebetween adjacent red sub-pixel regions “SPr” and between adjacent greensub-pixel regions “SPg” is increased such that a fabrication of theshadow mask becomes easy.

The deep blue sub-pixel region “SPb1”, the sky blue sub-pixel region“SPb2”, the deep blue sub-pixel region “SPb1” and the sky blue sub-pixelregion “SPb2” are respectively disposed in the second columns of thefirst to fourth pixel regions “P1” to “P4”. Since deep blue emittinglayer 436 in the deep blue sub-pixel region “SPb1” and sky blue emittinglayer 438 in the sky blue sub-pixel region “SPb2” are formed ofdifferent material, they can not be formed in one time. A shadow maskfor the deep blue and sky blue emitting layers 436 and 438 isillustrated below.

The red, green, deep blue and sky blue emitting layers 432, 434, 436 and438 are respectively formed in the red sub-pixel region “SPr”, the greensub-pixel region “SPg”, the deep blue sub-pixel region “SPb1” and thesky blue sub-pixel region “SPb2”. The red, green, deep blue and sky blueemitting layers 432, 434, 436 and 438 constitute an emitting diode (notshown) with a first electrode (not shown) and a second electrode (notshown). To prevent the shadowing problem, the emitting layers 432, 434,436 and 438 are spaced apart from each other by a first distance “d1”.Since there is no shadowing problem in the same color emitting layers,the same color emitting layers are spaced apart from each other by asecond distance “d2” being smaller than the first distance “d1”.

For example, when the red and green sub-pixel regions “SPr” and “SPg”are respectively disposed in the first and second rows of the firstcolumn in the first pixel region “P1” and the green and red sub-pixelregions “SPg” and “SPr” are respectively disposed in the first andsecond rows of the first column in the third pixel region “P3”, the redand green emitting layers 432 and 334 in the first pixel region “P1” andthe green and red emitting layers 434 and 432 in the third pixel region“P3” are spaced apart from each other by the first distance “d1”,respectively, and the green emitting layer 434 in the first pixel regionand the green emitting layer 434 in the third pixel region “P3” arespaced apart from each other by the second distance “d2” being smallerthan the first distance “d1”.

Accordingly, with the same size pixel region, a size of each of the redand green emitting layers 432 and 434 in the third embodiment is largerthan a size of each of the red and green emitting layers 232 and 234 inthe second embodiment.

Namely, each of the red and green emitting layers 432 and 434 has afirst width “w1”, which is equal to the first width “w1” in the secondembodiment, and a third height “h3”, which is larger than the firstheight “h1” in the second embodiment. Each of the deep blue emittinglayer 436 and the sky blue emitting layer 438 has the second width “w2”and the second height “h2” being larger than the second width “w2”.

In FIG. 12, the first width “w1” is larger than the third height “h3”.Alternatively, when the third height “h3” is further increased, thethird height “h3” may be larger than the first width “w1”.

The red, green, deep blue and sky blue emitting layers 432, 434, 436 and438 are formed by a thermal deposition using a shadow mask. In FIG. 12,the red, green, deep blue and sky blue emitting layers 432, 434, 436 and438 are overlapped portions of the first and second electrodes.

The deep blue emitting layer 436 and the sky blue emitting layer 438have an advantage and a disadvantage depending on properties of theemitting material. The deep blue emitting layer 436 has an advantage ina color reproductivity, while the sky blue emitting layer 438 has anadvantage in a life time and an emission efficiency.

In the OELD device 410, the deep blue and sky blue emitting layers 436and 438 are alternately arranged with each other to obtain advantages ofthe deep blue and sky blue emitting layers 436 and 438.

Namely, when the high color reproduction image is displayed, the deepblue emitting layer 436 except the sky blue emitting layer 438 isdriven. In this case, the red and green emitting layers 432 and 434 inthe second pixel region “P2” constitute one unit pixel “P21” with thedeep blue emitting layer 436 in the first pixel region “P1”. Namely, thered and green sub-pixel regions “SPr” and “SPg” in the first pixelregion “P1” and the red and green sub-pixel regions “SPr” and “SPg” inthe second pixel region “P2” share the deep blue sub-pixel region“SPb1”.

On the other hand, when a general image is displayed without the highcolor reproduction, the sky blue emitting layer 438 except the deep blueemitting layer 436 is driven. In this case, the red and green emittinglayers 432 and 434 in the second pixel region “P2” constitute one unitpixel “P22” with the sky blue emitting layer 438 in the second pixelregion “P2”. Namely, the red and green sub-pixel regions “SPr” and “SPg”in the first pixel region “P1” and the red and green sub-pixel regions“SPr” and “SPg” in the second pixel region “P2” share the sky bluesub-pixel region “SPb2”.

As mentioned above, the deep blue emitting layer 436 and the sky blueemitting layer 438 are selectively driven depending on the displayedimage. In this case, by using a rendering method, the unit pixel as aunit for displaying an image is varied.

In the OELD device 410 according to the fourth embodiment of the presentinvention, the first and second columns are defined by dividing each ofthe first to fourth pixel regions “P1” to “P4”, and the first and secondrows are defined by dividing the first column. The red and greensub-pixel regions “SPr” and “SPg” are alternately arranged in the firstcolumn. The red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other along the vertical direction andthe horizontal direction. In the first column of vertically adjacentpixel regions “P1” and “P3” or “P2” and “P4”, the same color sub-pixelregions are arranged to be closer than different color sub-pixelregions. The deep blue sub-pixel region “SPb1” and the sky bluesub-pixel region “SPb2” are respectively disposed in the second columnof one pixel region and in the second column of another one pixelregion. The red, green, deep blue and sky blue emitting layers 432, 434,436 and 438 are respectively formed in the red, green, deep blue and skyblue sub-pixel regions “SPr”, “SPg”, “SPb1” and “SPb2”.

Accordingly, with compared to the related art OELD device, where threesub-pixel regions are arranged along a direction, there is a margin inreduction of the width of the sub-pixel regions. As a result, there is amargin for requirement of a high resolution. Namely, when an area, e.g.,a width and a height, of the red, green, deep blue and sky bluesub-pixel regions “SPr”, “SPg”, “SPb1” and “SPb2” is reduced withrequirement of a high resolution, there is a margin in reduction of thearea of the red red, green, deep blue and sky blue sub-pixel regions“SPr”, “SPg”, “SPb1” and “SPb2” such that a shadow mask for forming thered, green, deep blue and sky blue emitting layers 432, 434, 436 and 438is easily fabricated.

In addition, the same color sub-pixel regions are closely arranged andclosely arranged sub-pixel regions corresponds to one opening portion ofthe shadow mask such that a size of each opening portion of the shadowmask and a distance between opening portions of the shadow mask isincreased. Moreover, by alternately arranging the red and greensub-pixel regions “SPr” and “SPg” along the horizontal direction, adistance between adjacent red sub-pixel regions “SPr” and betweenadjacent green sub-pixel regions “SPg” is increased. As a result, afabrication of the shadow mask used for the red and green emittinglayers 432 and 434 becomes easy.

Moreover, since the deep blue emitting layer 436 in the deep bluesub-pixel region “SPb1” and the sky blue emitting layer 438 in the skyblue sub-pixel region “SPb2” are formed in different process, a distancebetween the opening portions of the shadow mask for used the deep blueemitting layer 436 and the sky blue emitting layer 438 is increased suchthat a fabrication of the shadow mask used for the deep blue emittinglayer 436 and the sky blue emitting layer 438 becomes easy.

The shadow mask used for the deep blue emitting layer 436 and the skyblue emitting layer 438 is illustrated with FIG. 13. FIG. 13 is a viewshowing a shadow mask used for deep blue and sky blue emitting layers ofan OELD device according to the fourth embodiment of the presentinvention. The shadow mask used for the red and green emitting layers issame as that in the third embodiment.

Referring to FIG. 13 with FIG. 12, a shadow mask 470 used for formingthe deep blue emitting layer 436 and the sky blue emitting layer 438includes a plurality of opening portions 472 for transmitting anemitting material and a blocking portion 474. An align position of theshadow mask 470 for the deep blue emitting layer 436 is different froman align position of the shadow mask 470 for the sky blue emitting layer438. The shadow mask 470 is moved along a vertical direction or ahorizontal direction to form one of the deep blue and sky blue emittinglayers 436 and 438 after forming the other of the deep blue and sky blueemitting layers 436 and 438.

Each of the opening portions 472 corresponds to the deep blue emittinglayer 436 or the sky blue emitting layer 438 in the OELD device 410.Each of the opening portions 472 has a second width “w2” and a secondheight “h2”. Namely, each of the opening portions 472 has substantiallythe same size as the deep blue emitting layer 436 or the sky blueemitting layer 438. Alternatively, each of the opening portions 472 mayhave a size larger than the deep blue emitting layer 436 or the sky blueemitting layer 438.

The adjacent opening portions 472 of the shadow mask 470 are spacedapart from each other by a seventh length “L7” along a diagonaldirection. The seventh length “L7” is obtained by a summation of thefirst width “w1” and twice of the first distance “d1”, and the firstdistance “d1”. (L7˜((w1+2*d1)²+d1 ²)^(1/2) In addition, the adjacentopening portions 472 in the shadow mask 470 is space apart from eachother by an eighth length “L8” along a vertical direction. The eighthlength “L8” corresponds to a summation of twice of the second height“h2” of the deep blue emitting layer 436 or the sky blue emitting layer438 and twice of the first distance “d1”. (L8˜h2+2*d1)

Namely, a distance between adjacent opening portions 472 is increased,the shadow mask 470 is easily fabricated with a higher resolution. Inaddition, since the distances between adjacent opening portions 472along the vertical direction and the diagonal direction become close, athickness difference of the blocking portion 474 of the shadow mask 470is reduced such that deformation of the shadow mask 470 is prevented.

To further easily fabricate the shadow mask, the distance betweenopening portions is further increase by removing edges of each opening.FIG. 14 is a schematic view showing pixel regions of an OELD deviceaccording to a fifth embodiment of the present invention.

As shown in FIG. 14, an OELD device 510 includes first to fourth pixelregions “P1” to “P4” arranged in a matrix shape. Each of the first tofourth pixel regions “P1” to “P4” includes red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb”.

Each of the first to fourth pixel regions “P1” to “P4” has a rectangularshape to have a horizontal length “H” and a vertical length “V”. The redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in a first column of each of the first to fourth pixelregions “P1” to “P4”, and the blue sub-pixel region “SPb” is arranged ina second column of each of the first to fourth pixel regions “P1” to“P4”.

Each of the first to fourth pixel regions “P1” to “P4” is divided intothe first and second columns along a horizontal direction, and the firstcolumn is divided into first and second rows along a vertical direction.The red sub-pixel region “SPr” and the green sub-pixel region “SPg” arealternately arranged in the first and second rows of the first column.Namely, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe vertical direction. In other words, the red and green sub-pixelregions “SPr” and “SPg” are alternately arranged in the first column ofthe first and third pixel regions “P1” and “P3”. In addition, the redand green sub-pixel regions “SPr” and “SPg” are alternately arrangedwith each other in the first column of the second and fourth pixelregions “P2” and “P4”. As a result, in the first column, one greensub-pixel region “SPg” is positioned between two adjacent red sub-pixelregions “SPr”.

In the vertically-arranged pixel regions “P1” and “P3” or “P2” and “P4”,the same color sub-pixel regions are arranged to be closer thandifferent color sub-pixel regions. For example, when the red and greensub-pixel regions “SPr” and “SPg” are respectively disposed in the firstand second rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the thirdpixel region “P3”. In this case, a distance between the red and greensub-pixel regions “SPr” and “SPg” in each of the first and third pixelregions “P1” and “P3” is larger than that between the green sub-pixelregion “SPg” in the first pixel region “P1” and the green sub-pixelregion “SPg” in the second pixel region “P2”.

In addition, the red and green sub-pixel regions “SPr” and “SPg” arealternately arranged with each other in the pixel regions adjacent alongthe horizontal direction. For example, when the red and green sub-pixelregions “SPr” and “SPg” are respectively disposed in the first andsecond rows of the first column in the first pixel region “P1”, thegreen and red sub-pixel regions “SPg” and “SPr” are respectivelydisposed in the first and second rows of the first column in the secondpixel region “P2” which is adjacent to the first pixel region “P1” alongthe horizontal direction.

Similarly, the red and green sub-pixel regions “SPr” and “SPg” arerespectively arranged in the first and second rows of the first columnin the fourth pixel region “P4”. In this case, a distance between thered and green sub-pixel regions “SPr” and “SPg” in each of the secondand fourth pixel regions “P2” and “P4” is larger than that between thered sub-pixel region “SPr” in the second pixel region “P2” and the redsub-pixel region “SPr” in the fourth pixel region “P4”.

The same color sub-pixel regions are closely arranged and closelyarranged sub-pixel regions corresponds to one opening portion of theshadow mask such that a size of each opening portion of the shadow maskand a distance between opening portions of the shadow mask is increased.As a result, a fabrication of the shadow mask becomes further easy.

In addition, by alternately arranging the red and green sub-pixelregions “SPr” and “SPg” along the horizontal direction, a distancebetween adjacent red sub-pixel regions “SPr” and between adjacent greensub-pixel regions “SPg” is increased such that a fabrication of theshadow mask becomes easy.

The blue sub-pixel region “SPb” is positioned in the second column. Red,green and blue emitting layers 532, 534 and 536 are respectively formedin the red, green and blue sub-pixel regions “SPr”, “SPg” and “SPb”. Thered, green and blue emitting layers 532, 534 and 536 constitute anemitting diode (not shown) with a first electrode (not shown) and asecond electrode (not shown). To prevent the shadowing problem, theemitting layers 332, 334 and 336 are spaced apart from each other by afirst distance “d1”.

Since there is no shadowing problem in the same color emitting layers,the same color emitting layers are spaced apart from each other by asecond distance “d2” being smaller than the first distance “d1”. Forexample, the first distance “d1” may be about 22 micrometers.

For example, when the red and green sub-pixel regions “SPr” and “SPg”are respectively disposed in the first and second rows of the firstcolumn in the first pixel region “P1” and the green and blue sub-pixelregions “SPg” and “SPr” are respectively disposed in the first andsecond rows of the first column in the third pixel region “P3”, the redand green emitting layers 532 and 534 in the first pixel region “P1” andthe green and red emitting layers 534 and 532 in the third pixel region“P3” are spaced apart from each other by the first distance “d1”,respectively, and the green emitting layer 534 in the first pixel region“P1” and the green emitting layer 534 in the third pixel region “P3” arespaced apart from each other by the second distance “d2” being smallerthan the first distance “d1”.

Accordingly, with the same size pixel region, a size of each of the redand green emitting layers 532 and 534 in the third embodiment is largerthan a size of each of the red and green emitting layers 232 and 234 inthe second embodiment.

Two corners of each of the red and green emitting layers 532 and 534 areremoved. In each pixel region, first and second corners of the redemitting layer 532 and second and fourth corners, which respectivelyface the first and second corners, of the green emitting layer 534 areremoved. In other words, when two adjacent same color emitting layers invertically adjacent two pixel regions are defined one emitting layergroup, four outer corners of the one emitting layer group are removed.

For example, when the green emitting layer 534 is disposed in the secondrow of the first column in the first pixel region “P1” and in the firstrow of the first column in the third pixel region “P3”, four outercorners, i.e., upper two corners of the green emitting layer 534 in thesecond row of the first column in the first pixel region “P1” and lowertwo corners of the green emitting layer 534 in the first row of thefirst column in the third pixel region “P3”, of the emitting layer groupincluding two green emitting layers 534 are removed.

The removed portion may be an isosceles triangle having a side of “a”.To remove corners of the emitting layers means to change an exposed areaof the first electrode through the opening 128 a (of FIG. 5) of the bank128 (of FIG. 5).

Each of the red and green emitting layers 532 and 534 has a rectangularshape, which has a first width “w1” and a third height “h3” larger thanthe first height “h1” and corners of which are removed. Namely, each ofthe red and green emitting layers 532 and 534 has a modified hexagonalshape, and the emitting layer group has a modified octagonal shape. Theblue emitting layer 536 has the second width “w2” and the second height“h2” being larger than the second width “w2”.

In FIG. 14, the first width “w1” is larger than the third height “h3”.Alternatively, when the third height “h3” is further increased, thethird height “h3” may be larger than the first width “w1”.

As mentioned above, in the OELD device 510 according to the fifthembodiment of the present invention, the first and second columns aredefined by dividing each of the first to fourth pixel regions “P1” to“P4”, and the first and second rows are defined by dividing the firstcolumn. The red and green sub-pixel regions “SPr” and “SPg” arealternately arranged in the first column. The red and green sub-pixelregions “SPr” and “SPg” are alternately arranged with each other alongthe vertical direction and the horizontal direction. In the first columnof vertically adjacent pixel regions “P1” and “P3” or “P2” and “P4”, thesame color sub-pixel regions are arranged to be closer than differentcolor sub-pixel regions. The red, green and blue emitting layers 532,534 and 536 are respectively formed in the red, green and blue sub-pixelregions “SPr”, “SPg” and “SPb”.

Accordingly, with compared to the related art OELD device, where threesub-pixel regions are arranged along a direction, there is a margin inreduction of the width of the sub-pixel regions. As a result, there is amargin for requirement of a high resolution. Namely, when an area, e.g.,a width and a height, of the red, green and blue sub-pixel regions“SPr”, “SPg” and “SPb” is reduced with requirement of a high resolution,there is a margin in reduction of the area of the red, green and bluesub-pixel regions “SPr”, “SPg” and “SPb” such that a shadow mask forforming the red, green and blue emitting layers 532, 534 and 536 iseasily fabricated.

In addition, the same color sub-pixel regions are closely arranged andclosely arranged sub-pixel regions corresponds to one opening portion ofthe shadow mask such that a size of each opening portion of the shadowmask and a distance between opening portions of the shadow mask isincreased. Moreover, by alternately arranging the red and greensub-pixel regions “SPr” and “SPg” along the horizontal direction, adistance between adjacent red sub-pixel regions “SPr” and betweenadjacent green sub-pixel regions “SPg” is increased. As a result, afabrication of the shadow mask used for the red and green emittinglayers 542 and 544 becomes easy.

Moreover, two corners of each of the red and green emitting layers 532and 534 are removed such that a distance between adjacent openingportion of the shadow mask for the red and green emitting layers 532 and534 is increased. As a result, a fabrication of the shadow mask used forthe red and green emitting layers 542 and 544 becomes further easy.

In the OEDL device 510 according to the fifth embodiment of the presentinvention, the red and green emitting layers 532 and 534 are formedusing the above shadow mask. FIG. 15 is a view showing a shadow maskused for red and green emitting layers of an OELD device according tothe fifth embodiment of the present invention. The shadow mask used forthe blue emitting layer is same as that in the first to thirdembodiments.

Referring to FIG. 15 with FIG. 14, the shadow mask 560 used for formingthe red and green emitting layers 532 and 534 includes a plurality ofopening portions 562 for transmitting an emitting material and ablocking portion 564. An align position of the shadow mask 560 for thered emitting layer 532 is different from an align position of the shadowmask 560 for the green emitting layer 534. The shadow mask 560 is movedalong a vertical direction or a horizontal direction to form one of thered and green emitting layers 532 and 534 after forming the other of thered and green emitting layers 532 and 534.

Each of the opening portions 562 corresponds to two adjacent redemitting layers 532 or two adjacent green emitting layers 534 invertically adjacent pixel regions. Each of the opening portions 562 hasthe first width “w1” and a fourth height “h4”. The fourth height “h4” isequal to a summation of twice of the third height “h3” of the redemitting layer 532 or the green emitting layer 534 and the seconddistance “d2”. (h4˜2*h3+d2) Alternatively, the fourth height “h4” may belarger than a summation of heights of two adjacent red emitting layers532 and a distance between two adjacent red emitting layers 532.

Each of the opening portions 562 corresponds to one emitting layergroup. Namely, each of the opening portions 562 corresponds to twoadjacent red emitting layers 532. Four corners of the rectangular shapeare removed such that each of the opening portions 562 has a modifiedoctagonal shape. The removed portion may be an isosceles triangle havinga side of “a”. For example, “a” may be larger than about 3 micrometers.

Accordingly, the adjacent opening portions 562 in the shadow mask 560 isspace apart from each other along a diagonal direction by a ninth length“L9”. The ninth length “L9” is larger than the fifth length “L5” (ofFIG. 11) as much as twice of a height of removed triangle.(L9˜(((w2+2*d1)²+d1 ²)^(1/2)+2*a/2^(1/2)) In addition, the adjacentopening portions 562 in the shadow mask 560 is space apart from eachother along a vertical direction by a sixth length “L6” corresponding toa summation of twice of the third height “h3” of the red emitting layer532 or the green emitting layer 534, twice of the first distance “d1”and the second distance “d2”. (L6˜2*h3+2*d1+d2)

The fourth height “h4” of each opening portion 562 is larger than thefirst height “h1” of each of the opening portions 162 and 262 in thefirst and second embodiments, and the sixth length “L6”, which is adistance between vertically adjacent opening portions 562, is largerthan the second length “L2”, which is a distance between verticallyadjacent opening portions 162 and 262, in the first and secondembodiments.

In addition, the ninth length “L9”, which is a diagonal distance betweenadjacent opening portions 562, is larger than the fifth length “L5”,which is a diagonal distance between adjacent opening portions 362 and462, in the third and fourth embodiments.

Accordingly, a distance between adjacent opening portions 562 and a sizeof the opening portion 562 are increased, the shadow mask 560 is easilyfabricated with a higher resolution. In addition, since the distancesbetween adjacent opening portions 562 along the vertical direction andthe diagonal direction become close, a thickness difference of theblocking portion 564 of the shadow mask 560 is reduced such thatdeformation of the shadow mask 560 is prevented.

As mentioned above, in the OELD device according to the presentinvention, the red and green sub-pixel regions are alternately arrangedin a first column of the pixel region and the blue sub-pixel region isarranged in a second column of the pixel region such that there areadvantages in an aperture ratio and a resolution. In addition, the samecolor sub-pixel regions in vertically adjacent pixel region are closelyarranged such that a fabrication of the shadow mask becomes easy.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. An organic electroluminescent display device, comprising: first to fourth pixel regions each including red, green and blue sub-pixel regions, each of the first to fourth pixel regions being divided into first and second columns, and the first column being divided into first and second rows, wherein a red sub-pixel region and a green sub-pixel region are respectively arranged in the first and second rows, and a blue sub-pixel region is arranged in the second column; a red emitting layer formed in the red sub-pixel region; a green emitting layer formed in the green sub-pixel region; and a blue emitting layer formed in the blue sub-pixel region, wherein the red sub-pixel region has a first rectangular shape having a first vertical length and a first horizontal length being larger than the first vertical length, and the green sub-pixel region has a second rectangular shape having a second vertical length and a second horizontal length being larger than the second vertical length, and wherein the blue sub-pixel region has a third rectangular shape having a third horizontal length and a third vertical length being larger than the third horizontal length.
 2. The device according to claim 1, wherein the red and green sub-pixel regions in horizontally adjacent pixel regions are alternately arranged with each other.
 3. The device according to claim 2, wherein a shadow mask used for forming the red and green emitting layers includes a plurality of opening portions corresponding to one of the red and green emitting layers and a blocking portion surrounding the plurality of opening portions.
 4. The device according to claim 1, wherein one of the red and green emitting layers is positioned in the second row of the first pixel region and in the first row of the third pixel region, which is vertically adjacent to the first pixel region, and a first distance between two adjacent red emitting layers or two adjacent green emitting layers in the first and third pixel region is smaller than a second distance between the green emitting layer and the red emitting layer in the first pixel region or the third pixel region.
 5. The device according to claim 4, wherein a shadow mask used for forming the red and green emitting layers includes a plurality of opening portions corresponding to the two adjacent red emitting layers or the two adjacent green emitting layers and a blocking portion surrounding the plurality of opening portions.
 6. The device according to claim 4, wherein the two adjacent red emitting layers or the two adjacent green emitting layers form an emitting layer group, and four outer corners of the emitting layer group is removed such that the emitting layer group has an octagonal shape.
 7. The device according to claim 4, wherein a third distance between each of the red and green emitting layer and the blue emitting layer in the first pixel region is equal to the second distance.
 8. The device according to claim 1, wherein the blue sub-pixel region includes a deep blue sub-pixel region and a sky blue sub-pixel region, and the blue emitting layer includes a deep blue emitting layer and a sky blue emitting layer respectively formed in the deep blue emitting and the sky blue emitting layer, and wherein the deep blue and sky blue sub-pixel regions are alternately arranged with each other along a vertical direction and a horizontal direction.
 9. The device according to claim 8, wherein a shadow mask used for forming the deep blue emitting layer and the sky blue emitting layer includes a plurality of opening portions corresponding to the deep blue emitting layer or the sky blue emitting layer and a blocking portion surrounding the plurality of opening portions.
 10. The device according claim 1, further comprising: a first electrode under each of the red, green and blue emitting layers; a bank on edges of the first electrode and including an opening, wherein the opening exposes a portion of the first electrode; and a second electrode on the red, green and blue emitting layers, wherein each of the red, green and blue emitting layers corresponds to the exposed portion of the first electrode. 